Vessel Wall Reaction after Vena Cava Filter Placement

Abstract

Purpose: To evaluate the interaction between the Cordis Keeper vena caval filter and vessel wall in a porcine model. Methods: Implantation of the filter was performed in five pigs. Radiologic data concerning inferior vena cava (IVC) diameter and filter patency, filter leg span, and stability were collected. At 2 or 6 months post-implantation, histopathologic analysis of the IVC wall was performed. Results: All filters remained patent with no evidence of migration. However, at 6 months follow-up, two legs of one filter penetrated the vessel wall and were adherent to the liver. These preliminary results suggest that with the observed gradual increase in the filter span, the risk of caval wall penetration increases with time, especially in a relatively small IVC (average diameter 16 mm). Conclusion: The Cordis Keeper filter was well tolerated, but seems to be prone to caval wall penetration in the long term.